zsh+OSX: how to cope w spaces in fnames? [PART 2]

This is a follow-up to a post of mine of a few months ago (message-id:
fii7gq$erf$1@reader1.panix.com). There I wrote:

> I recently switched to OS X for my home computer. One recurrent
> source of headaches is the proliferation in OS X of filenames with
> embedded spaces. This means that many of my habitual shell
> interaction practices fail; e.g. anything like

> % for i ( *.mp3 ) frobnicate $i

> will fail with errors like

> frobnicate: La: No such file or directory
> frobnicate: Cucaracha.mp3: No such file or directory

> etc.

As several responders correctly pointed out at the time, this
shouldn't happen with zsh (which, happily, is the shell I use).

My example, in fact, was chosen a bit too hastily. It is not
globbing that causes me problems but rather command substitutions:

% for i ( $( some_command ) ) frobnicate "$i"

In this case, if the individual results produced by some_command
themselves contain whitespace (as happens often in OS X whenever
these results are filenames), the loop variable will be set to
invalid values.

In my pre-OS X days, I used command substitutions *all the time*.
It's one of my all-time favorite techniques. How can I recover
it (short of ditching OS X or renaming my files, of course)?

TIA!

kj

--
NOTE: In my address everything before the first period is backwards;
and the last period, and everything after it, should be discarded.

Re: zsh+OSX: how to cope w spaces in fnames? [PART 2]

On Sun, 27 Jan 2008 19:52:37 +0000 (UTC), kj wrote:
[...]
> % for i ( $( some_command ) ) frobnicate "$i"
>
> In this case, if the individual results produced by some_command
> themselves contain whitespace (as happens often in OS X whenever
> these results are filenames), the loop variable will be set to
> invalid values.
>
> In my pre-OS X days, I used command substitutions *all the time*.
> It's one of my all-time favorite techniques. How can I recover
> it (short of ditching OS X or renaming my files, of course)?
[...]

IFS=$'\n'

for i ($(some_command)) frobnicate $i

(but note that \n is a valid character in a file name).

Or you could also do:

for i (${(f)"$(some_command)"}) frobnicate $i

(f) is a parameter expansion flag which is a short cut for
ps:\n:

"p" is to an expansion flag to recognise prompt expansion in the
s flag. s:\n: is to split on \n.

--
Stephane

Re: zsh+OSX: how to cope w spaces in fnames? [PART 2]

In <479ce85d$0$899$ba4acef3@news.orange.fr> Stephane Chazelas writes:

>On Sun, 27 Jan 2008 19:52:37 +0000 (UTC), kj wrote:
>[...]
>> % for i ( $( some_command ) ) frobnicate "$i"
>>
>> In this case, if the individual results produced by some_command
>> themselves contain whitespace (as happens often in OS X whenever
>> these results are filenames), the loop variable will be set to
>> invalid values.
>>
>> In my pre-OS X days, I used command substitutions *all the time*.
>> It's one of my all-time favorite techniques. How can I recover
>> it (short of ditching OS X or renaming my files, of course)?
>[...]

>IFS=$'\n'

>for i ($(some_command)) frobnicate $i

>(but note that \n is a valid character in a file name).

>Or you could also do:

>for i (${(f)"$(some_command)"}) frobnicate $i

>(f) is a parameter expansion flag which is a short cut for
>ps:\n:

>"p" is to an expansion flag to recognise prompt expansion in the
>s flag. s:\n: is to split on \n.

Thanks! I should have known the first option you proposed (although
I'd have probably used something more naive like IFS="\n"), but it
doesn't matter: I like your second solution better because it is
more targeted (no need to worry about the possible unwanted side
effects on frobnicate from having IFS set to $'\n').

Parameter expansion flags are still terra incognita for me... Time
to hit the docs!

kynnjo

--
NOTE: In my address everything before the first period is backwards;
and the last period, and everything after it, should be discarded.